Cableless connection apparatus and method for communication between chassis

ABSTRACT

Apparatus and methods for cableless connection of components within chassis and between separate chassis. Pairs of Extremely High Frequency (EHF) transceiver chips supporting very short length millimeter-wave wireless communication links are configured to pass radio frequency signals through holes in one or more metal layers in separate chassis and/or frames, enabling components in the separate chassis to communicate without requiring cables between the chassis. Various configurations are disclosed, including multiple configurations for server chassis, storage chassis and arrays, and network/switch chassis. The EHF-based wireless links support link bandwidths of up to 6 gigabits per second, and may be aggregated to facilitate multi-lane links.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent applicationSer. No. 14/244,475, filed on Apr. 3, 2014, entitled “CABLELESSCONNECTION APPARATUS AND METHOD FOR COMMUNICATION BETWEEN CHASSIS”,which is hereby incorporated herein by reference in its entirety and allpurposes.

BACKGROUND INFORMATION

Ever since the introduction of the microprocessor, computer systems havebeen getting faster and faster. In approximate accordance with Moore'slaw (based on Intel® Corporation co-founder Gordon Moore's 1965publication predicting the number of transistors on integrated circuitsto double every two years), the speed increase has shot upward at afairly even rate for nearly three decades. At the same time, the size ofboth memory and non-volatile storage has also steadily increased, suchthat many of today's personal computers are more powerful thansupercomputers from just 10-15 years ago. In addition, the speed ofnetwork communications has likewise seen astronomical increases.

Increases in processor speeds, memory, storage, and network bandwidthtechnologies have resulted in the build-out and deployment of networkswith ever increasing capacities. More recently, the introduction ofcloud-based services, such as those provided by Amazon (e.g., AmazonElastic Compute Cloud (EC2) and Simple Storage Service (S3)) andMicrosoft (e.g., Azure and Office 365) has resulted in additionalnetwork build-out for public network infrastructure, in addition to thedeployment of massive data centers to support these services that employprivate network infrastructure.

Cloud-based services are typically facilitated by a large number ofinterconnected high-speed servers, with host facilities commonlyreferred to as server “farms” or data centers. These server farms anddata centers typically comprise a large-to-massive array of rack and/orblade servers housed in specially-designed facilities. Many of thelarger cloud-based services are hosted via multiple data centers thatare distributed across a geographical area, or even globally. Forexample, Microsoft Azure has multiple very large data centers in each ofthe United States, Europe, and Asia. Amazon employs co-located andseparate data centers for hosting its EC2 and AWS services, includingover a dozen AWS data centers in the US alone.

In order for the various server blades and modules to communicate withone another and to data storage, an extensive amount of cabling is used.Installing the cabling is very time-consuming and prone to error. Inaddition, the cost of the cables and connectors themselves aresignificant. For example, a 3-foot SAS (Serial attached SCSI) cable maycost $45 alone. Multiply this by thousands of cables and installations,and the costs add up quickly, as does the likelihood of cabling errors.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of thisinvention will become more readily appreciated as the same becomesbetter understood by reference to the following detailed description,when taken in conjunction with the accompanying drawings, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified:

FIG. 1 is a diagram illustrate a radio frequency antenna output emittedfrom a transmitter EHF transceiver chip and being received by a receiverEHF transceiver chip;

FIG. 2 is a block diagram of one embodiment of an EHF transceiver chip;

FIGS. 3a-3d illustrate launch orientations between pairs of EHFtransceiver chips, wherein FIG. 3a depicts a vertical launch, FIG. 3bdepicts an offset vertical launch, FIG. 3c depicts a side launch, andFIG. 3d depicts a diagonal launch;

FIGS. 4a and 4b illustrate a millimeter-wave wireless link betweenrespective EHF transceiver chips in a blade server chassis above astorage array chassis under which signals are passed through holes inthree metal layers, according to one embodiment;

FIG. 4c illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a blade server chassis above a storage arraychassis under which signals are passed through holes in one plasticlayer and two metal layers, according to one embodiment;

FIG. 4d illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a storage array chassis above a blade serverchassis under which signals are passed through holes in three metallayers, according to one embodiment;

FIG. 4e illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a storage array chassis above a blade serverchassis under which signals are passed through holes in two metallayers, according to one embodiment;

FIG. 4f illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a storage array chassis above a blade serverchassis under which signals are passed through a hole in one metallayer, according to one embodiment;

FIGS. 5a and 5b illustrate a millimeter-wave wireless link betweenrespective EHF transceiver chips in a network/switch chassis above ablade server chassis under which signals are passed through holes inthree metal layers, according to one embodiment;

FIG. 5c illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a network/switch chassis above a blade serverchassis under which signals are passed through one plastic layer andholes in two metal layers, according to one embodiment;

FIG. 5d illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a network/switch chassis above a blade serverchassis under which signals are passed through holes in two metallayers, according to one embodiment;

FIG. 5e illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a network/switch chassis above a blade serverchassis with an open top under which signals are passed through holes intwo metal layers, according to one embodiment;

FIG. 5f illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a network/switch chassis above a blade serverchassis under which signals are passed through a hole in one metallayer, according to one embodiment;

FIG. 6 is a graphic diagram depicting an electromagnetic field strengthof signals emitted from a transmitting EHF transceiver chip and passingthrough holes in two metal layers using a vertical launch configuration;

FIG. 7 is a graphic diagram depicting an electromagnetic field strengthof signals emitted from a transmitting EHF transceiver chip and passingthrough holes in three metal layers using a diagonal launchconfiguration;

FIGS. 8a and 8b illustrate a configuration under which an array of EHFtransceiver chips in a server chassis are wirelessly linked with anarray of EHF transceiver chips in a storage chassis below the serverchassis, according to one embodiment;

FIGS. 9a and 9b illustrated a modified version of the configuration ofFIGS. 8a and 9b further adding four fabric backplanes with EHFtransceiver chips on both sides in the server chassis, according to oneembodiment;

FIGS. 10a and 10b illustrate a configuration under which components in amiddle server chassis are enabled to wirelessly communicate withcomponents in storage chassis above and below the server chassis,according to one embodiment;

FIGS. 11a and 11b illustrate a configuration under which a 6 U serverchassis is disposed below a network/switch chassis and above a storagearray, according to one embodiment;

FIGS. 12a and 12b respective show topside and underside isometricperspective views of a storage array employing an upper backplaneincluding an array of EHF transceiver chips, according to oneembodiment;

FIG. 12c shows a topside isometric perspective view of a storage arrayemploying EHF transceiver chips mounted to vertical boards to whichstorage drives are coupled, according to one embodiment;

FIG. 12d illustrates a backplane configured for use in a storage arrayincluding an array of SATA connectors on its topside and an array of EHFtransceiver chips on its underside;

FIGS. 13a and 13b illustrate a backplane configured for use in anetwork/switch chassis, according to one embodiment;

FIG. 14a shows a network switch chassis implementing the backplane ofFIGS. 13a and 13 b;

FIG. 14b shows a network switch chassis implementing two backplanes ofFIGS. 13a and 13b under which the upper backplane is inverted;

FIG. 15 illustrates a server module including a pair of EHF transceiverchips mounted to its main PCB board, according to one embodiment; and

FIG. 16 is a schematic diagram illustrating a technique for combiningmultiple millimeter-wave wireless links in parallel to increase linkbandwidth, according to one embodiment.

DETAILED DESCRIPTION

Embodiments of apparatus and methods for cableless connection ofcomponents within chassis and between separate chassis are describedherein. In the following description, numerous specific details are setforth to provide a thorough understanding of embodiments of theinvention. One skilled in the relevant art will recognize, however, thatthe invention can be practiced without one or more of the specificdetails, or with other methods, components, materials, etc. In otherinstances, well-known structures, materials, or operations are not shownor described in detail to avoid obscuring aspects of the invention.

For clarity, individual components in the Figures herein may also bereferred to by their labels in the Figures, rather than by a particularreference number. Additionally, reference numbers referring to aparticular type of component (as opposed to a particular component) maybe shown with a reference number followed by “(typ)” meaning “typical.”It will be understood that the configuration of these components will betypical of similar components that may exist but are not shown in thedrawing Figures for simplicity and clarity or otherwise similarcomponents that are not labeled with separate reference numbers.Conversely, “(typ)” is not to be construed as meaning the component,element, etc. is typically used for its disclosed function, implement,purpose, etc.

In accordance with aspects of the embodiments disclosed herein,Extremely High Frequency (EHF) wireless communication links are used inplace of conventional cabling techniques, resulting in reductions inboth system component costs and labor costs. The Extremely HighFrequency range is approximately 30 GHz-300 GHz. The embodimentsleverage recent advancements in very short length millimeter-wavewireless transceiver chips to facilitate contactless communication linksfor blade server and other high-density module configurations applicablefor data centers and the like. Additionally, the embodiments facilitateuse of existing and future server blade and server moduleconfigurations.

FIG. 1 illustrates radio frequency (RF) signal energy being output by anantenna in a first EHF transceiver chip 100 operating as a transmitter(Tx or TX) and being received by a second EHF transceiver chip 102 thatis operating as a receiver (Rx or RX). As illustrated by the darkershading representing higher energy density, the electromagnetic fieldstrength of the RF signal dissipates with distance from the transmitter.

In one embodiment, each of EHF chips 100 and 102 comprise EHF chipsmanufactures by WaveConnex, Inc., Mountainview, Calif. In oneembodiment, the EHF chips illustrated in the Figures herein comprise aWaveConnex WCX102 (or WCX102b) transceiver chip. Details of thestructure and operations of the millimeter-wave technology implementedin the WaveConnex chips are disclosed in U.S. Pat. No. 8,554,136entitled “TIGHTLY-COUPLED NEAR-FIELD COMMUNICATION-LINKCONNECTOR-REPLACEMENT CHIPS,” and U.S. application Ser. No. 13/471,052(U.S. Pub. No. 2012/0286049 A1) and Ser. No. 13/471,058 (U.S. Pub. No.2012/0290760 A1), both entitled “SCALABLE HIGH-BANDWIDTH CONNECTIVITY.”

FIG. 2 shows a block diagram 200 of an embodiment of an EHF transceiverchip. The basic chip blocks includes a Tx baseband block 202, RF blocks204, and an Rx baseband block 206. The RF blocks include an EHFtransmitter block 208, an EHF receiver block 210, and an antenna 212.The EHF chip is configured to receive a stream of data to be transmittedfrom an external component using a differential signal at pins TXinP(positive) and TXinN (negative). The input transmitted digital stream isprocessed by Tx baseband block 202 and EHF transmitter block 208 tocreate a modulated RF signal that is radiated output from antenna 212.Antenna 212 also receives signals transmitted from a paired EHFtransceiver of similar configuration (not) shown, with the receivedsignals processed by EHF receiver block 210 and Rx baseband block 206 togenerate a received bitstream encoded using differential signaling thatis output at the RXoutP and RXoutN pins. In one embodiment, the EHFtransceiver chip employs a 60 GHz carrier that is generated on-chip,with the modulated signal sent to antenna 212 for transmission.

The EHF transceiver chip includes multiple control inputs 214 that areused for various control and configuration purposes. The control inputsenable the transceiver chip to be configured in two operating modes,including a high-speed mode, intended for use with DC balanceddifferential signals that is suitable for signals running from 100 Mb/sto 6.0 Gb/s and features support for envelope-based Out-of-Band (OOB)signaling used in Serial-Attached-SCSI (SAS) and Serial AdvancedTechnology Attachment (SATA), as well as electrical idle and LowFrequency Periodic Signaling (LFPS) signals in Peripheral ComponentInterconnect Express (PCIe) and Universal Serial Bus version 3.0 (USB3.0).

The EHF transceiver chips are configured to facilitate very short rangewireless communication links between pairs of transceiver chips invarious orientations. For example, a pair of chips may be configuredwith the top surfaces opposite one another as shown by the verticallaunch configuration of FIG. 3a . As shown in FIG. 3b , the antennas ofa pair of EHF transceiver chips do not need to be in alignment. FIG. 3cshows a configuration under which a pair of EHF transceiver chips 100and 102 are in substantially the same plane. In addition to thisconfiguration, a pair of EHF transceiver chips can be in respectiveparallel planes that are closely spaced (e.g., within a 5-15millimeters). As shown in FIG. 3d , a diagonal launch configuration isalso supported.

In accordance with further aspects of some embodiments, EHF transceiverchips are configured to support a plurality of very short lengthmillimeter-wave wireless links between circuitry and components inphysically separate enclosures, such as chassis employed in standard 19″racks. By way of example and without limitation, a configuration 400 isshown in FIGS. 4a and 4b under which circuitry on a server blade 402 ina blade server chassis 404 is linked in communication with a disk drive406 in a storage array chassis 408. In further detail, server blade 402includes a main board 410 to which an EHF transceiver chip 412 ismounted. As an option, an EHF transceiver chip may be mounted to adaughter board or otherwise comprise part of a multi-board module. Inthe illustrated embodiment of FIG. 4a , server blade 402 is eithermounted within an enclosure including a cover plate 414 or is coupled tothe cover plate 414 in which a hole 416 is formed. Similarly-sized holes418 and 420 are respectively formed in the sheet metal baseplate 422 ofblade server chassis 404 an in a top plate 424 of storage array 408.Preferably, holes 416, 418, and 420 are substantially aligned to form anopen pathway 426 through cover plate 414, baseplate 422 and top plate424, enabling transmission of RF energy between EHF transceiver chip 412and an EHF transceiver 428 mounted to a backplane 430 in storage arraychassis 408. Baseplate 430 includes a plurality of Serial ATA (SATA)connectors 432 to which disk drive 406 is connected.

In one embodiment, EHF transceiver chip 428 is configured to performsignaling to support a SATA interface to facilitate communicationbetween disk drive 406 and the EHF transceiver chip using the SATAprotocol. Accordingly, configuration 400 enables circuitry on serverblade 410 to write data to and read data from a disk drive 406 in aseparate chassis via an EHF millimeter-wave bi-directional wireless link434. As a result, configuration 400 removes the need for use of physicalcabling between blade server chassis 404 and storage array chassis 408.

Exemplary variations of configuration 400 are shown in FIGS. 4c, 4d, 4e,and 4f . Under a configuration 400 c of FIG. 4c , a server blade 402 ais mounted within an enclosure including a plastic cover plate 415 orotherwise cover plate 415 is attached to main board 410. Unlike metals,which generally attenuate RF signals in the EHF frequency range, variousplastics may be employed that provide substantially insignificantattenuation. Accordingly, there is no hole formed in cover plate 415 inthe illustrated embodiment. Alternatively, a hole could be formed incover plate 415 depending on the attenuation of the cover plate materialin the EHF frequency range.

Under configurations 400 d, 400 e and 400 f of respective FIGS. 4d, 4e,and 4f , the storage array chassis 408 is placed above blade serverchassis 404, and the rest of the components are generally flippedvertically. Configuration 400 d is similar to configuration 400, andincludes the passing of EHF millimeter-wave bi-directional wireless link434 via an open pathway formed by holes 416, 418, and 420 through coverplate 414, baseplate 422 and top plate 424.

Under some blade server chassis configuration, blade servers or servermodules are inserted vertically and may be “hot-swapped” without havingto power down the entire chassis. In addition, there are similar bladeserver chassis configurations under which the chassis does not include atop or cover plate, since this would need to be removed to remove orinstall server blades or modules. Such a configuration 400 e is shown inFIG. 4e , wherein blade server chassis 404 a does not include a coverplate. In this instance, RF signals to facilitate EHF millimeter-wavebi-directional wireless link 434 only need to pass through two metalsheets corresponding to base plate 424 of storage array chassis 408 anda cover plate 423 of a server blade 402 b. The also reduces the distancebetween EHF transceiver chips 412 and 428.

Under configuration 400 f shown in FIG. 4f , the RF signals only need topass through a single metal sheet corresponding to the base plate 424 ofstorage array chassis 408. In this configuration, a blade server 402 cdoes not include a cover plate. Optionally, the server blade or modulecould include a plastic cover plate (not shown) through which a hole mayor may not be formed. As with blade server chassis 404 a in FIG. 4e ,blade server chassis 404 b does not include a cover plate.

FIGS. 5a-5f illustrate various configurations under which server bladesin a blade server chassis are enabled to wirelessly communicate withnetworking and/or switching components in a separate chassis. Forexample, FIGS. 5a and 5b illustrate a configuration 500 under which aserver blade 502 in a blade server chassis 504 is enabled to communicatewith networking circuitry on a backplane 506 in a network/switch chassis508 via a an EHF millimeter-wave bi-directional wireless link 510facilitated by a pair of EHF transceiver chips 512 and 514. As before,EHF transceiver chip 512 is mounted to a main board 516 (ordaughterboard or similar) of server blade 502, which includes either anenclosure having a cover plate 518 or cover plate 518 is coupled to mainboard 516. The other two sheet metal layers illustrated in FIGS. 5a and5b correspond to a blade server chassis cover plate 520 and a bottomplate 522 of network/switch chassis 508. Respective holes 524, 526, and528 are formed in cover plate 518, cover plate 520, and bottom plate522, thereby creating an open pathway 530 through which EHFmillimeter-wave bi-directional wireless link 510 RF signals propagate.

Configuration 500 c of FIG. 5c illustrates a server blade or module 502a that employs a plastic cover plate 519 rather than a metal coverplate. As above, depending on the attenuation of EHF RF signals by theplastic material, a hole through the cover plate may or may not need tobe formed. Under a configuration 500 d of FIG. 5d , server blade ormodule 502 b does not employ a cover plate. Under a configuration 500 eshown in FIG. 5e , blade server chassis 504 a does not employ a coverplate, while server blade or module 502 c employs a metal cover plate521 with a hole 527 formed through it. Optionally, cover plate 521 couldbe made of plastic and may or may not include a hole (not shown). Undera configuration 500 f of FIG. 5f , neither blade server chassis 504 anor server blade/module 502 d employ a cover plate. Thus, the RF signalsfor EHF millimeter-wave bi-directional wireless link 510 only need topass through a single metal sheet corresponding to bottom plate 522 ofnetwork/switch chassis 508.

As with any RF signal, the strength of the EHF millimeter-wave signal isa function of the RF energy emitted for the RF source (e.g., antenna)and the spectral attributes of the signal. In turn, the length of thewireless link facilitated between a pair of EHF transceiver chips willdepend on the amount of RF energy received at the receiver's antenna andsignal filtering and processing capabilities of the EHF receivercircuitry. In one embodiment, the aforementioned WCX100 chip supportsmultiple power output levels via corresponding control inputs via one ormore of control pins 214. Under one embodiment, the distance between EHFtransceiver chips is 2-15 mm, noting that this is merely exemplary andnon-limiting. Generally, higher data transmission link bandwidth may beachieved when the link's pair of EHF transceiver chips are closertogether and/or using more power.

To verify link performance capabilities and expectations under some ofthe embodiments disclosed herein, computer-based RF modeling wasperformed. Under one approach, the computational software (ANSYS HFSS)generated a visual representation of the signal strength of the RFsignals emitted from a transmitting EHF transceiver chip. The modelsalso considered the effect of the metal sheets/plates between pairs ofEHF transceiver chips under various configurations.

A snapshot 600 of the RF energy pattern for a configuration under whichthe RF signal emitted from a transmitting EHF transceiver chip 602 ismodeled as passing through two metal sheets 604 and 606 before beingreceived by a receiving EHF transceiver chip 608 is shown in FIG. 6. Themodel graphically illustrates the electro-magnetic field energy level indecibels. FIG. 7 shows a snapshot 700 of the RF energy pattern for aconfiguration under which the RF signal emitted from a transmitting EHFtransceiver chip 702 is modeled as passing through three metal sheets704, 706 and 708 before being received by a receiving EHF transceiverchip 710. In addition to these configurations, various otherconfigurations were modeled, including variations in the size of theholes in the metal sheets/plates, the number of metal sheets/plates, thedistance between the pair of EHF transceiver chips, the orientation ofthe EHF transceiver chips (e.g., vertical launch, side launch, diagonallaunch, amount of alignment offset, etc.).

Generally, the teachings and principles disclosed herein may beimplemented to support wireless communication between components inseparate chassis that are adjacent to one another (e.g., one chassis ontop of another chassis in the rack). Various non-limiting examples ofconfigurations supporting wireless communication between chassis usingEHF transceiver chips are shown in FIGS. 8a, 8b, 9a, 9b, 10a, 10b, 11a,11b, 12a, 12b, 13a , 13 b, 14 a, and 14 b. It will be understood thatthe configurations shown in these figures are simplified to emphasizethe millimeter-wave wireless communication facilitated through use ofEHF transceiver chips. Accordingly, these illustrative embodiments mayshow more or less EHF transceiver chips than might be implemented, andactual implementations would include well-known components that are notshown for convenience and simplicity in order to not obscure theinventive aspects depicted in the corresponding Figures. In addition,the illustrated embodiment may not be to scale, and may present partialor transparent components to reveal other components that wouldotherwise be obscured.

In a configuration 800 of FIGS. 8a and 8b , an array of server modules802 are mounted to backplanes 804, 806, 808, and 810 in an upper serverchassis 812. In one exemplary embodiment, server modules 802 comprisingIntel® Avoton™ servers modules. Meanwhile, a plurality of storage drives814 are coupled to backplanes 816, 818, 820, and 822 in a lower storagechassis 824. Each of backplanes 804, 806, 808, and 810 contain an arrayof downward-facing EHF transceiver chips 826, while each of backplanes816, 818, 820, and 822 contain an array of upward-facing EHF transceiverchips 828, wherein the arrays of the EHF transceiver chips areconfigured such that the downward-facing EHF transceiver chips arealigned respective upward-facing EHF transceiver chips on a pairwisebasis. In addition to what is shown in FIGS. 8a and 8b , there would bearrays of holes (not shown) in a bottom 830 of upper chassis 812 and acover plate (not shown) of lower storage chassis 824.

FIGS. 9a and 9b show a configuration 1000 under which a server chassis812 a comprising a modified version of server 812 is installed above astorage chassis 824. As illustrated, server chassis 812 now furtherincludes four fabric backplanes 904, 906, 908 and 910 disposed belowbackplanes 804, 806, 808, and 810. Each of fabric backplanes 904, 906,908 and 910 includes an array of upward-facing EHF transceiver chips 912mounted to its topside an array of downward-facing EHF transceiver chips914 mounted to its underside. Upward-facing EHF transceiver chips 828are configured to be substantially aligned with downward-facingtransceiver chips 826 on backplanes 804, 806, 808, and 810. Similarly,downward-facing EHF transceiver chips 914 are configured to besubstantially aligned with upward-facing transceiver chips on 828 onbackplanes 816, 818, 820, and 822.

FIG. 10a shows a configuration 1000 under which a middle server chassis1002 is sandwiched between an upper storage chassis 1004 and a lowerstorage chassis 1006, with further details of middle server chassis 1002depicted in FIG. 10b . Server chassis 1002 includes server boardassemblies 1026, each including a backplane 1010 to which variouscomponents are mounted on a topside thereof including a processor 1012,a plurality of memory modules 1014, and an InfiniBand host bus adaptor(HBA) 1016. Processor 1012 is generally illustrative of one or moreprocessors that may be included with each server board assembly 1008. Anarray of EHF transceiver chips 1020 are mounted to the underside of eachbackplane 1010. In addition, there would be a hole pattern having aconfiguration similar to the EHF transceiver chips 1020 in the baseplate 1022 of a chassis frame 1024 (not shown for clarity).

As shown in FIG. 10a , server chassis 1002 also includes an upper set offour backplanes 1026, each including an array of upward-facing EHFtransceiver chips 1028. In one embodiment, backplanes 1026 arecommunicatively coupled to backplanes 1010 via some form of physicalconnections, such as but not limited to connectors between pairs ofbackplanes or ribbon cables. In the illustrated embodiments, pairs ofupper and lower backplanes are each connected to an HBA 1016 thatfurther supports communication between the backplanes.

Lower storage chassis 1006 is generally configured in a similar mannerto lower storage chassis 824, except the shape of each of fourbackplanes 1030 is different than backplanes 816, 818, 820, and 822. Asbefore, an array of upward-facing EHF transceiver chips 1032 is mountedto each backplane 1030, while a plurality of storage drives 1034 arecoupled to an underneath side of the backplanes via applicableconnectors. There also would be an array of holes in the cover plate oflower storage chassis 1006 (not shown) that would be aligned with thearray of EHF transceiver chips 1032.

Upper storage chassis 1004 is generally configured in a similar mannerto lower storage chassis 1006, but with its vertical orientationflipped. As a result, each of four backplanes 1036 include a pluralityof storage devices 1038 coupled to its topside, and an array ofdownward-facing EHF transceiver chips 1040. Upper storage chassis 1004would also have an array of storage drives 1038.

FIGS. 11a and 11b illustrate a configuration 1100 including a 6 U bladeserver chassis 1102 disposed under a switch chassis 1104 and above astorage array 1006. As shown in FIG. 11b , arrays of holes are formed ina cover plate 1108 of storage array 1006 and in a base plate 1110 ofswitch chassis 1004. Each of a plurality of server blades 1112 installedin blade server chassis 1102 includes a frame having an upper plate 1114and a lower plate 1116 through which a plurality of holes are formedadjacent to EHF transceiver chips along the top and bottom edges of theserver blade's main board (not shown), which is mounted to the frame. Inaddition, the cover and base plate of blade server chassis 1102 (notshown) will also include a plurality of holes that are substantiallyaligned with the holes in upper plate 1114 and lower plate 1116 whenblade servers 1112 are installed in server chassis 1002.

FIGS. 12a and 12b show further details of storage array 1106, accordingto one embodiment. A plurality of storage drives 1200 are mounted to andcommunicatively coupled with (e.g., via SATA connectors) vertical boards1202. In turn, the vertical boards 1202 are communicatively coupled witha backplane 1204 including an array of EHF transceiver chip 1206. In theillustrated embodiment, storage drives comprise 2½ inch drives that aremounted back to back. Storage drives having other form factors, such as3½ inch drives may be used in other embodiments.

FIG. 12c shows an embodiment of a storage array 1106 a. Under theillustrated configuration, EHF transceiver chips 1208 are mounted towardthe top of vertical boards 1202. In the illustrated embodiment one EHFtransceiver chip 1208 is implemented for each drive; however, this ismerely exemplary, as multiple EHF transceiver chips may be used for oneor more drive. Also in the illustrated embodiment the EHF transceiverchips 1208 are mounted on a single side of vertical boards 1202;optionally, EHF transceiver chips may be mounted on both sides of thevertical boards.

As shown in FIG. 12d , in one embodiment a plurality of SATA connectors1210 are mounted to a backplane 1212 having an array of EHF transceiverchips 1214. In one configuration, backplane 1212 is disposed in thebottom of a chassis with SATA connectors 1210 pointing upward and EHFtransceiver chips 1214 pointing downward. In another configuration,backplane 1212 is inverted and disposed toward the top of a chassis withEHF transceiver chips 1214 pointing upward and SATA connectors 1210pointing downward.

EHF transceiver chips may be implemented in networking related chassis,such as switch chassis and network chassis or a network/switch chassisthat includes components supporting networking and switching functions.Generally, a network/switch chassis may employ a single backplane or twobackplanes arrayed with EHF transceiver chips, such as illustrated by anetwork/switch backplane 1300 in FIGS. 13a and 13b . In this example, aplurality of Ethernet network connectors 1302 comprising RJ45 Ethernetjacks are mounted on a topside of network/switch backplane 1300, whilean array of EHF transceiver chips 1304 are mounted on the underside ofthe backplane. Wire traces in network/switch backplane 1300 are routedto network connectors 1302 and a multi-port network/switch chip 1304.Although only a single multi-port network/switch chip is shown, it willbe understood that multiple chips of similar configuration may beimplemented on a network/switch backplane, and that network ports andswitch operations may also be implemented on separate chips or otherwiseusing separate circuitry and logic. Multi-port network/switch chip 1304also is connected via wire traces in network/switch backplane 1300 toEHF transceiver chips 1306. In addition, applicable interface circuitryand signal-conditioning circuitry (not shown) may be implemented usingtechniques and principles well-known in the art.

The terminology network/switch is meant to convey the apparatus may beimplemented for networking and switching functions. Depending on theparticular system needs or architecture, a network/switch chassis mayinclude various numbers of external network ports that are used tointerface with other servers, storage devices, etc. in other chassisand/or other racks, such as 4, 8, 12, 16, 24, etc. In someimplementations, a network/switch backplane may be configured to supportswitching functionality related to internal communications in a mannersimilar to some switch cards used in data centers and the like.

FIGS. 14a and 14b respectively show exemplary 1 U network/switch chassisthat support wireless connections with a chassis below (fornetwork/switch chassis 1400 a) and with both a chassis above and below(for a network/switch chassis 1400 b). As shown in FIG. 14a , anetwork/switch backplane 1300 is mounted within a 1 U chassis frame1402, with network connectors 1302 mounted toward the rear of thechassis frame. Network/switch chassis 1400 b further adds a secondnetwork/switch backplane 1300 a this is mounted such that EHFtransceiver chips 1404 are just below a top) of 1 U chassis frame 1402in which a plurality of holes 1308 are defined proximate to each EHFtransceiver chip.

A server module 1500 configured to facilitate wireless communicationwith components in another chassis is shown in FIG. 15. Server module1500 includes four CPU subsystems comprising Systems on a Chip (SoCs)1502 a, 1502 b, 1502 c, and 1502 d, each coupled to respective memories1504 a, 1504 b, 1504 c, and 1504 d. Each of SoCs 1502 a, 1502 b, 1502 c,and 1502 d is also communicatively coupled to PCIe interface 1506 via arespective PCIe link. Each of SoCs 1502 a, 1502 b, 1502 c, and 1502 dalso has access to an instruction storage device that containsinstructions used to execute on the processing cores of the SoC.Generally, these instructions may include both firmware and softwareinstructions, and may be stored in either single devices for a module,or each SoC may have its own local firmware storage device and/or localsoftware storage device. As another option, software instructions may bestored on one or more mass storage modules and accessed via an internalnetwork during module initialization and/or ongoing operations.

Each of the illustrated components are mounted either directly or via anapplicable socket or connector to a printed circuit board (PCB) 1510including wiring (e.g., layout traces and vias) facilitating transfer ofsignals between the components. This wiring includes signal paths forfacilitating communication over each of the PCIe links depicted in FIG.15. PCB 1510 also includes wiring for connecting selected components tocorresponding pin traces on an edge connector 1512. In one embodiment,edge connector 1512 comprises a PCIe edge connector, although this ismerely illustrative of one type of edge connector configuration and isnot to be limiting. In addition to an edge connector, an arrayed pinconnector may be used, and the orientation of the connector on thebottom of PCB 1510 in FIG. 15 is exemplary, as an edge or arrayed pinconnector may be located at an end of the PCB, which is a commonconfiguration for a blade server.

As further shown in FIG. 15, server module 1500 includes a pair of EHFtransceiver chips 1508 that are mounted toward the top edge of PCB 1510.This configuration is similar to that shown by Server Blade/Module 402in FIG. 4d , Server Blade/Module 402 b in FIG. 4e , and ServerBlade/Module 402 c in FIG. 4f . In general, a server module thatsupports communication via millimeter-wave wireless links may employ oneor more EHF transceiver chips, which may be mounted on one or both sidesof the modules main board and/or a daughterboard or the like.

FIG. 16 illustrates an example of combining multiple individualmillimeter-wave EHF links in parallel to support increased transferrates across communication interfaces. In the illustrated embodiment, aserver module 1500 a includes a four lane (4×) PCIe interface 1506, andis coupled to a PCIe connector 1600 supporting four (or more) PCIelanes. Pins corresponding to respective PCIe differential signal pairsare coupled to the differential TX input pins on each of a first set ofEHF transceiver chips 1602, which are wirelessly linked in communicationwith EHF transceiver chips 1604 on a pairwise basis. In turn, thedifferential RX output pins on EHF transceiver chips 1604 are coupled todifferential signal pair I/O pins on a PCIe interface chip 1606. Ingeneral, the technique illustrated in FIG. 16 may be used to support ann× PCIe link wherein n is an integer number of lanes greater than one.For example, standard PCIe multi-lane links may be implemented, such as2×, 4×, 8×, 16×, etc. PCIe links.

Embodiments implementing the principles and teachings herein provideseveral advantages over conventional approach. First, by facilitatingmillimeter-wave wireless links between EHF transceiver chips disposed inseparate chassis, components that are directly or indirectlycommutatively coupled to EHF transceiver chips are enabled to pass datato and receive data from components in other chassis without using acable connected between the chassis. This results in a cost savings, andalso prevents wiring errors such as might result when connecting a largenumber of cables between chassis in a rack. Since the EHF transceiverchips are mounted to backplanes and other circuit boards, theirimplement can be mass produced at a relatively low marginal cost(compared to similar components without the chips). Additionally, sinceno cable connections are required chassis can be easily removed forracks for maintenance such as replacement or upgrade of server blades ormodules without having to disconnect and then reconnect the cables orotherwise need to employ extra cable lengths to allow for maintenance ofchassis components.

Further aspects of the subject matter describe herein are set out in thefollowing numbered clauses:

Clause 1. An apparatus, comprising:

-   -   a first chassis, configured to be installed in a rack and        including a sheet metal base in which a first plurality of holes        are formed and having a backplane mounted therein parallel to        the sheet metal base and including a first plurality of        extremely high frequency (EHF) transceiver chips mounted to its        underside, each EHF transceiver chip disposed proximate to a        respective hole in the sheet metal base; and    -   a second chassis, configured to be installed in the rack and        including at least one of a plurality of blades or modules,        wherein at least a portion of the blades or modules includes an        EHF transceiver chip that is configured to communicate with a        respective EHF transceiver chip in the first plurality of EHF        transceiver chips when the first and second chassis are        installed in the rack to implement a plurality of        millimeter-wave wireless links facilitated by respective pairs        of EHF transceiver chips, wherein radio frequency signals for        each millimeter-wave wireless link pass through a respective        hole in the sheet metal base of the first chassis.

Clause 2. The apparatus of clause 1, wherein the first backplanecomprises a storage array backplane including a plurality of Serial ATA(SATA) connectors.

Clause 3. The apparatus of clause 2, wherein at least a portion of theSATA connectors are communicatively coupled to at least one EHFtransceiver chip via traces in the first backplane.

Clause 4. The apparatus of any of the proceeding clauses, wherein thefirst chassis comprises a network/switch chassis, and the firstbackplane includes switching circuitry and logic communicatively coupledto the first plurality of EHF transceiver chips via traces in the firstbackplane.

Clause 5. The apparatus of any of the proceeding clauses, wherein thefirst plurality of EHF transceiver chips are configured in atwo-dimensional array.

Clause 6. The apparatus of any of the proceeding clauses, wherein atleast one millimeter-wave wireless link facilitated by a pair of EHFtransceiver chips has a bandwidth of 6 Gbps.

Clause 7. The apparatus of any of the proceeding clauses, wherein theEHF transceiver chips use a 60 GHz carrier frequency.

Clause 8. The apparatus of any of the proceeding clauses, furtherwherein the second chassis includes a sheet metal top having a secondplurality of holes formed therein, and wherein when the first and secondchassis are installed in the rack the first plurality and secondplurality of holes are aligned, wherein radio frequency signals for eachmillimeter-wave wireless link pass through a respective pair of alignedholes in the sheet metal base of the first chassis and the sheet metaltop of the second chassis.

Clause 9. The apparatus of any of the proceeding clauses, furtherwherein at least one server blade or module has an EHF transceiver chipmounted on or operatively coupled to a main board and a metal plate orenclosure operatively coupled to the main board, and the metal plate orenclosure has a hole proximate to the EHF transceiver chip, and whereinradio frequency signals for each millimeter-wave wireless link for theat least one server blade or module pass through the a respective pairof holes in the metal plate or enclosure and the sheet metal base of thefirst chassis.

Clause 10. The apparatus of any of the proceeding clauses, furthercomprising a rack, wherein the first and second chassis are installed inthe rack.

Clause 11. An apparatus, comprising:

-   -   a first chassis, configured to be installed in a first slot of a        rack and including a sheet metal base in which a first plurality        of holes are formed and having a first backplane mounted therein        proximate and parallel to the sheet metal base and including a        first plurality of extremely high frequency (EHF) transceiver        chips mounted to its underside, each EHF transceiver chip        disposed proximate to a respective hole in the sheet metal base;    -   a second chassis, configured to be installed in the rack in a        second slot beneath the first slot having a second backplane        mounted therein including a second plurality of EHF transceiver        chips mounted to its upward-facing side when the second chassis        is installed in the rack,    -   wherein when the first and second chassis are installed in the        rack EHF transceiver chips from among the first plurality of EHF        transceiver chips are disposed opposite respective EHF        transceiver chips from among the second plurality of EHF        transceiver chips on a pairwise basis and wherein upon operation        of respective pairs of EHF transceiver chips disposed opposite        of one another, a plurality of millimeter-wave wireless        communication links are facilitated via radio frequency signals        that pass through a respective hole in the sheet metal base of        the first chassis.

Clause 12. The apparatus of clause 11, wherein the second server chassisincludes a sheet metal top having a second plurality of holes formedtherein, each hole proximate to a respective EHF transceiver chip amongthe second plurality of receiver chips in the second backplane, andwherein when the first and second chassis are installed in the rackrespective pairs of holes in the first and second plurality of holes arealigned, and wherein radio frequency signals for each of a plurality ofmillimeter-wave wireless links pass through a respective pair of holesin the sheet metal top of the second chassis and the sheet metal base ofthe first chassis.

Clause 13. The apparatus of clause 11 or 12, wherein the first chassiscomprises a server chassis including at least one backplane to which oneof server components are mounted or including a plurality of connectorsconfigured to couple with a respective connector for a server blade orserver module that may be installed in the first chassis, wherein eachof the at least one backplanes includes a plurality of EHF transceiverchips mounted to its underside.

Clause 14. The apparatus of any of clauses 11-13, wherein the firstchassis comprises a server chassis including at least one backplane towhich a plurality of server blades or server modules are communicativelycoupled, wherein each of the at least one backplanes includes aplurality of EHF transceiver chips mounted to its underside, and whereineach EHF transceiver chip is communicatively coupled to a server bladeor server module.

Clause 15. The apparatus of any of clauses 11-14, wherein the secondchassis comprises a storage chassis including a plurality of storagedrives that are communicatively coupled to the second backplane.

Clause 16. The apparatus of clause 15, wherein multiple storage drivesare mounted to a vertical board that in turn is communicatively coupledto the second backplane via a connector.

Clause 17. The apparatus of any of clauses 11-16, wherein the secondchassis comprises a network/switch chassis, and the second backplaneincludes switching circuitry and logic communicatively coupled to thefirst plurality of EHF transceiver chips via traces in the firstbackplane.

Clause 18. The apparatus of any of clauses 11-17, wherein each of thefirst plurality of EHF transceiver chips and the second plurality of EHFtransceiver chips are configured in a respective two-dimensional array.

Clause 19. The apparatus of any of clauses 11-18, wherein the EHFtransceiver chips use a 60 GHz carrier frequency.

Clause 20. An apparatus comprising:

-   -   a chassis frame including a metal base plate in which a        plurality of holes are formed; and    -   a backplane, mounted to the chassis frame proximate to the metal        base plate, having a plurality of extremely high frequency (EHF)        transceiver chips mounted to its underside that are        communicatively coupled to switching circuitry mounted on the        backplane and a plurality of network connectors that are mounted        on the backplane and communicatively coupled to the switching        circuitry,    -   wherein the plurality of EHF transceiver chips are aligned with        the plurality of holes formed in the metal base plate.

Clause 21. The apparatus of clause 20, wherein the plurality of holesand the plurality of EHF transceiver chips are configured in alignedtwo-dimensional patterns.

Clause 22. The apparatus of clause 20 or 21, wherein the backplanecomprises a first backplane, and wherein the apparatus further comprisesa second backplane, having a similar configuration to the firstbackplane and mounted in the chassis frame toward a metal top platehaving a second plurality of holes formed therein,

-   -   wherein an orientation of the second backplane is        vertically-flipped relative to an orientation of the first        backplane such that a second plurality of EHF transceiver chips        mounted to the second backplane are on a topside of the second        backplane and the second plurality of EHF transceiver chips are        aligned with respective holes in the metal top plate.

Clause 23. The apparatus of clause 22, further comprising a connectionmeans for communicatively coupling the first backplane to the secondbackplane.

Clause 24. An apparatus, comprising:

-   -   a blade server including;    -   a frame having an upper plate and a lower plate in which a        plurality of holes are formed    -   a main server board, mounted to the frame and to which a        plurality of components are operatively coupled, including,    -   at least one processor;    -   memory;    -   a first plurality of extremely high frequency (EHF) transceiver        chips, each disposed proximate to a respective hole in the upper        plate; and    -   a second plurality of EHF transceiver chips, each disposed        proximate to a respective hole in the lower plate,    -   wherein each of the EHF transceiver chips is communicatively        coupled either directly or indirectly with a processor.

Clause 25. The apparatus of clause 24, further comprising anInput/Output (I/O) interface that is either integrated in a processor orcomprising a separate component to which at least one processor iscoupled, wherein at least a portion of the EHF transceiver chips arecommunicatively coupled to the I/O interface.

Clause 26. The apparatus of clause 25, wherein the I/O interfacecomprises a Peripheral Component Interconnect Express (PCIe) interface,and wherein the PCIe interface is coupled to multiple EHF transceiverchips and the apparatus is configured to implement a multi-lane PCIelink by sending PCIe differential signals for respective lanes to therespective EHF transceiver chips in parallel.

Clause 27. The apparatus of any of clauses 24-26, further comprising:

-   -   a chassis, including a plurality of slots configured to receive        a respective blade server having a similar configuration to the        blade server of clause 21, the chassis further including a        bottom plate and a top plate, each having a plurality of rows        with multiple holes formed therein, wherein when a blade server        is installed in a slot in the chassis the holes in the lower        plate of the frame are aligned with respective holes in the        bottom plate of the chassis and the holes in the upper plate of        the frame are aligned with respective holes in the top plate of        the chassis.

Clause 28. An apparatus comprising:

-   -   a backplane including a plurality of Peripheral Component        Interconnect Express (PCIe) connectors on a first side and a        plurality of extremely high frequency (EHF) transceiver chips        mounted to a second side, wherein at least one PCIe connector is        communicatively coupled to transmit input pins and receive        output pins on each of n EHF transceiver chips in a first set of        EHF transceiver chips; and    -   control logic on the backplane for implementing a multi-lane nx        PCIe link between a server blade or server module including a        first PCIe interface and a second PCIe interface on a second        apparatus that is coupled to transmit input pin and receive        output pins on each of n EHF transceiver chips in a second set        of EHF transceiver chips when the server blade or server module        is installed in the backplane, the first set of EHF transceiver        chips are disposed within a signaling range of the second set of        EHF transceiver chips and the first and second apparatus are        operating, wherein respective pairs of EHF transceiver chips in        the first and second sets of EHF transceiver chips are        configured to implement respective millimeter-wave wireless        links, and wherein n>1.

Clause 29. The apparatus of clause 28, wherein the EHF transceiver chipsare configured to support a link bandwidth of up to 6 gigabits persecond.

Clause 30. The apparatus of clause 28 or 29, wherein the first pluralityof EHF transceiver chips are configured in a first pattern, and whereinthe apparatus further comprises a chassis frame including a metal baseplate through which a plurality of holes are formed having a secondpattern, wherein the backplane is mounted to the chassis frame proximateto the metal base plate and the first and second pattern of holes arealigned.

Clause 31. A method, comprising:

-   -   communicatively coupling at a first component in a first chassis        installed in a rack to a second component in a second chassis        installed in the rack immediately above or below the first        chassis via at least one pair of extremely high frequency (EHF)        transceiver chips configured to transmit and receive        millimeter-wave radio frequency (RF) signals,    -   wherein, for each of the at least one pair of EHF transceiver        chips, a first EHF transceiver chip is operatively coupled to        the first component in the first chassis and a second EHF        transceiver chip is operatively coupled to the second component        in the second chassis.

Clause 32. The method of clause 31, wherein each of the millimeter-waveRF signals pass through at least one hole in at least one of the firstchassis and second chassis.

Clause 33. The method of clause 31 or 32, wherein at least a portion ofthe millimeter-wave RF signals pass through respective pairs of holes inthe first and second chassis.

Clause 34. The method of any of clauses 31-33, wherein the secondcomponent is contained in a metal chassis having a first hole, andmillimeter-wave RF signals to facilitate communication between the firstcomponent and the second component pass through the first hole, a secondhold in the second chassis, and a third hole in the first chassis.

Clause 35. The method of any of clauses 31-34, further comprisingcommunicatively coupling the first component in a first chassis to aplurality of second chassis components in the second chassis includingthe second component, wherein each of the second chassis components iscommunicatively coupled to the first chassis component using at leastone pair of EHF transceiver chips.

Clause 36. The method of clause 35, wherein the plurality of secondcomponents comprise storage devices.

Clause 36. The method of clause 35, wherein the plurality of secondcomponents comprise server blades or server modules.

Clause 37. The method of any of clauses 31-36, wherein the firstcomponent comprises a backplane having an first side to which aplurality of EHF transceiver chips are mounted, wherein the backplane islocated proximate to one of a baseplate or top plate in the firstchassis having a plurality of holes, and wherein the plurality of EHFtransceiver chips are configured in a first pattern and the plurality ofholes are configured in a second pattern substantially matching thefirst pattern.

Clause 38. The method of any of clauses 31-36, wherein the firstcomponent comprises a storage array backplane having a first side onwhich a plurality of EHF transceiver chips are mounted and a second sideon which a plurality of Serial ATA (SATA) connectors are mounted.

Clause 39. The method of any of clauses 31-36, wherein the first chassiscomprises a network/switch chassis, and the first component comprises abackplane includes switching circuitry and logic communicatively coupledto a plurality of EHF transceiver chips via traces in the backplane.

Clause 40. The method of any of clauses 31-39, wherein each pair of EHFtransceiver chips facilitate a respective millimeter-wave wireless link,and wherein at least one millimeter-wave wireless link has a bandwidthof 6 Gbps.

Clause 41. The method of any of clauses 31-40, wherein the EHFtransceiver chips use a 60 GHz carrier frequency.

Clause 42. A method comprising,

-   -   communicatively coupling a first backplane to a second backplane        via a plurality of millimeter-wave radio frequency (RF) signals        transmitted between pairs of extremely high frequency (EHF)        transceiver chips, wherein for each pair of EHF transceiver        chips a first EHF transceiver chip is mounted to the first        backplane and a second EHF transceiver chip is mounted to the        second backplane and each pair of EHF transceiver chips        facilitate a respective millimeter-wave RF link.

Clause 43. The method of clause 42, wherein the first backplane ismounted in a first chassis and the second backplane is mounted in asecond chassis, wherein the first chassis includes a baseplate having afirst plurality of holes and the second chassis includes a top plateincluding a second plurality of holes, and wherein signals for eachmillimeter-wave RF link pass through a respective hole in each of thebaseplate and top plate.

Clause 44. The method of clause 43 or 44, wherein the EHF transceiverchips use a 60 GHz carrier frequency.

Clause 45. The method of any of clauses 42-44, wherein, wherein a firstplurality of EHF transceiver chips are mounted to the first backplaneand configured in a first pattern and a second plurality of EHFtransceiver chips are mounted to the second backplane and configured ina pattern matching the first pattern.

Clause 46. A method comprising:

-   -   facilitating communication between a first plurality of        components coupled to a backplane in a first chassis with a        second plurality of components in a second chassis via a        plurality of millimeter-wave radio frequency communication links        implemented between pairs of extremely high frequency (EHF)        transceiver chips, wherein each pair of EHF transceiver chip        includes a first EHF transceiver chip mounted to the backplane        and a second EHF transceiver chip operatively coupled to one of        the plurality of components in the second chassis

Clause 47. The method of clause 46, wherein the first plurality of EHFtransceiver chips are configured in a two-dimensional array.

Clause 48. The method of clause 46 or 47, wherein at least a portion ofthe second plurality of components in the second chassis comprisestorage drives.

Clause 49. The method of any of clauses 46-48, wherein the backplanecomprises a server backplane.

Clause 50. The method of any of clauses 46-49, wherein the first chassiscomprises a server chassis and the second chassis comprises a storagearray.

Although some embodiments have been described in reference to particularimplementations, other implementations are possible according to someembodiments. Additionally, the arrangement and/or order of elements orother features illustrated in the drawings and/or described herein neednot be arranged in the particular way illustrated and described. Manyother arrangements are possible according to some embodiments.

In each system shown in a figure, the elements in some cases may eachhave a same reference number or a different reference number to suggestthat the elements represented could be different and/or similar.However, an element may be flexible enough to have differentimplementations and work with some or all of the systems shown ordescribed herein. The various elements shown in the figures may be thesame or different. Which one is referred to as a first element and whichis called a second element is arbitrary.

In the description and claims, the terms “coupled” and “connected,”along with their derivatives, may be used. It should be understood thatthese terms are not intended as synonyms for each other. Rather, inparticular embodiments, “connected” may be used to indicate that two ormore elements are in direct physical or electrical contact with eachother. “Coupled” may mean that two or more elements are in directphysical or electrical contact. However, “coupled” may also mean thattwo or more elements are not in direct contact with each other, but yetstill co-operate or interact with each other.

An embodiment is an implementation or example of the inventions.Reference in the specification to “an embodiment,” “one embodiment,”“some embodiments,” or “other embodiments” means that a particularfeature, structure, or characteristic described in connection with theembodiments is included in at least some embodiments, but notnecessarily all embodiments, of the inventions. The various appearances“an embodiment,” “one embodiment,” or “some embodiments” are notnecessarily all referring to the same embodiments.

Not all components, features, structures, characteristics, etc.described and illustrated herein need be included in a particularembodiment or embodiments. If the specification states a component,feature, structure, or characteristic “may”, “might”, “can” or “could”be included, for example, that particular component, feature, structure,or characteristic is not required to be included. If the specificationor claim refers to “a” or “an” element, that does not mean there is onlyone of the element. If the specification or claims refer to “anadditional” element, that does not preclude there being more than one ofthe additional element.

As used herein, a list of items joined by the term “at least one of” canmean any combination of the listed terms. For example, the phrase “atleast one of A, B or C” can mean A; B; C; A and B; A and C; B and C; orA, B and C.

The above description of illustrated embodiments of the invention,including what is described in the Abstract, is not intended to beexhaustive or to limit the invention to the precise forms disclosed.While specific embodiments of, and examples for, the invention aredescribed herein for illustrative purposes, various equivalentmodifications are possible within the scope of the invention, as thoseskilled in the relevant art will recognize.

These modifications can be made to the invention in light of the abovedetailed description. The terms used in the following claims should notbe construed to limit the invention to the specific embodimentsdisclosed in the specification and the drawings. Rather, the scope ofthe invention is to be determined entirely by the following claims,which are to be construed in accordance with established doctrines ofclaim interpretation.

What is claimed is:
 1. An apparatus, comprising: a first chassis,configured to be installed in a first slot in a standardized 19 inchrack and including a sheet metal base in which a first plurality ofholes are formed and having a backplane mounted therein parallel to thesheet metal base, the backplane including a first plurality of extremelyhigh frequency (EHF) transceiver chips mounted to its underside, eachEHF transceiver chip disposed proximate to a respective hole in thesheet metal base; and a second chassis, configured to be installed in asecond slot in the rack beneath the first slot and including a pluralityof blades or modules, wherein at least a portion of the blades ormodules includes an EHF transceiver chip that is configured tocommunicate with a respective EHF transceiver chip in the firstplurality of EHF transceiver chips when the first and second chassis areinstalled in the rack to implement a plurality of millimeter-wavewireless links facilitated by respective pairs of EHF transceiver chips,wherein radio frequency signals for each millimeter-wave wireless linkpass through a respective hole in the sheet metal base of the firstchassis.
 2. The apparatus of claim 1, wherein the backplane comprises astorage array backplane including a plurality of Serial ATA (SATA)connectors.
 3. The apparatus of claim 2, wherein at least a portion ofthe SATA connectors are communicatively coupled to at least one EHFtransceiver chip via traces in the backplane.
 4. The apparatus of claim1, wherein the first chassis comprises a network/switch chassis, and thebackplane includes switching circuitry and logic communicatively coupledto the first plurality of EHF transceiver chips via traces in thebackplane.
 5. The apparatus of claim 1, wherein the first plurality ofEHF transceiver chips are configured in a two-dimensional array.
 6. Theapparatus of claim 1, wherein at least one millimeter-wave wireless linkfacilitated by a pair of EHF transceiver chips has a bandwidth of 6Gbps.
 7. The apparatus of claim 1, wherein the EHF transceiver chips usea 60 GHz carrier frequency.
 8. The apparatus of claim 1, further whereinthe second chassis includes a sheet metal top having a second pluralityof holes formed therein, and wherein when the first and second chassisare installed in the rack the first plurality and second plurality ofholes are aligned, wherein radio frequency signals for eachmillimeter-wave wireless link pass through a respective pair of alignedholes in the sheet metal base of the first chassis and the sheet metaltop of the second chassis.
 9. The apparatus of claim 1, further whereinat least one server blade or module has an EHF transceiver chip mountedon or operatively coupled to a main board and a metal plate or enclosureoperatively coupled to the main board, and the metal plate or enclosurehas a hole proximate to the EHF transceiver chip, and wherein radiofrequency signals for each millimeter-wave wireless link for the atleast one server blade or module pass through a respective pair of holesin the metal plate or enclosure and the sheet metal base of the firstchassis.